The invention relates to a rotor for a gas turbine. Furthermore, the invention relates to a gas turbine having a rotor.
Modern gas turbines, particularly modern airplane engines, have to meet the highest demands with respect to reliability, weight, power, economic efficiency and durability. In the development of engines of this type which meet the above-mentioned requirements, various criteria have to be observed. For example, reference is made here to aerodynamics, vibration mechanics, stability and wave dynamics as well as production engineering and material science.
Gas turbines, particularly airplane engines, consist of several assemblies. The combustion chamber, the fan, the high-pressure turbine as well as the low-pressure turbine and the high-pressure compressor as well as the low-pressure compressor should be mentioned here as assemblies of gas turbines. The high-pressure compressor, the low-pressure compressor, the high-pressure turbine as well as the low-pressure turbine, as a rule, comprise several stages. In the case of the fan, a bladed fan rotor rotates with respect to a stationary fan housing. In the case of the compressor, particularly a high-pressure compressor and a low-pressure compressor, as well as in the case of the turbine, particularly the high-pressure turbine and the low-pressure turbine, a bladed rotor also rotates with respect to a stationary stator. The blades assigned to a turbine rotor or compressor rotor which rotate together with the rotor are called moving blades. These moving blades of the rotating rotor rotate relative to stationary guide blades assigned to the stator.
During the rotation of a bladed rotor with respect to a stationary stator, particularly a stationary housing or stationary guide blades, the stationary assemblies are excited to carry out vibrations as a result of the movement of the rotor. However, vibrations within the gas turbine or the airplane engine are disadvantageous because, as a result of the vibrations, the assemblies of the gas turbine are subjected to increased stress and thus to increased wear. Particularly resonance vibrations should be avoided. A gas turbine should therefore also be optimized with respect to the vibration mechanics.
In view of the above, the present invention is based on the problem of creating a novel rotor for a gas turbine as well as a corresponding gas turbine which are optimized with respect to vibration mechanics.
According to the invention, the blades of the rotor within the blade ring or within each blade ring are arranged at a different distance or a different blade pitch with respect to one another. As a result, it is ensured that the frequency at which the idle assemblies are excited to vibrate will change. Resonance vibrations are therefore avoided.
According to an advantageous further development of the invention, in the case of diametrically opposite blades, the distance to the respective next blade situated in front as well as the distance to the respective next blade situated in the rear is the same. The spacing of the blades within the blade ring or within each blade ring is dimensioned such that imbalances cancel each other out. This also has vibration-mechanical advantages.
Preferred further developments of the invention are indicated in the following description.